Физика список научных статей
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DOPING A SILICON SINGLE CRYSTAL WITH TERBIUM THROUGH DIFFUSION.
Using the diffusion method, monocrystalline samples of silicon doped with Thulium were prepared at 1250 degrees Celsius for 50 hours. The samples were found to have p-type conductivity after high-temperature annealing. After this process, the samples changed their type of conductivity from p-type...
2024 / Saidimov Ya.A., Rumi R.F., Umarov F.B. -
ИЗМЕРЕНИЕ ПРОСТРАНСТВЕННОГО РАСПРЕДЕЛЕНИЯ ИНТЕГРАЛЬНОГО КОЭФФИЦИЕНТА ИЗЛУЧЕНИЯ МАТЕРИАЛОВ, НАГРЕТЫХ ОТ 100 ДО 250 °С
В данной статье исследуется пространственное распределение интегрального коэффициента излучения (𝜀Т) материалов, нагретых до температур от 100 до 250 °C. Основное внимание уделено изменению этого коэффициента в зависимости от угла падения излучения (𝜙). Для измерений был разработан специальный...
2024 / А.C. Ильин, А.В. Гусев, К.А. Маилян, А.В. Глущенков, А.В. Киселев, А.В. Качанов -
Numerical Simulation of the Nonstationary Process of the Shot Based on the Navier – Stokes Equations
This paper gives a spatial mathematical formulation of the problem of internal ballistics based on the Navier – Stokes equations, taking into account the swirl of the flow due to the rotation of the projectile. The k-e model of turbulent viscosity is used. The control volume method is used for the...
2022 / I. G.Rusyak, V.A.Tenenev, S.A.KorolevScopusВАКRSCIMathSciNetzbMATH -
Direct Numerical Simulation of Aerodynamic Flows Based on Integration of the Navier – Stokes Equations
The results of the theoretical solution of aerodynamic problems based on direct numerical simulation by integrating the Navier – Stokes equations without involving additional models and empirical constants are shown. Modern approaches to the theoretical study of high-speed flows are determined. The ...
2022 / A. M. Lipanov, S.A.KarskanovScopusВАКRSCIMathSciNetzbMATH -
Investigation of the Structure of Waves Generated by a δ-perturbation of the Surface of a Capillary Jet
The wave capillary flow of the surface of an inviscid capillary jet, initiated by a single δ-perturbation of its surface, is studied. It is shown that the wave pattern has a complex structure. The perturbation generates both fast traveling damped waves and a structure of nonpropagating...
2022 / A. A. SafronovScopusВАКRSCIMathSciNetzbMATH -
Direct Numerical Simulation of Fully Developed Turbulent Gas–Particle Flow in a Duct
Direct numerical simulation of a fully developed turbulent flow of a viscous compressible fluid containing spherical solid particles in a channel is carried out. The formation of regions with an increased concentration of solid particles in a fully developed turbulent flow in a channel with solid...
2022 / V.N.Emelyanov, K.N.VolkovScopusВАКRSCIMathSciNetzbMATH -
Nonlinear Effects of Krypton Flow in a Micronozzle with a Cylindrical Tube
This paper considers krypton flow in a micronozzle with a cylindrical tube. A standardized conical nozzle elongated with cylindrical portion performs gas discharge into a vacuum chamber at a pressure of 10−2 Pa. Under such conditions, a low temperature area is formed in the central part of the jet...
2022 / M.A.Korepanov, M.R.Koroleva, E.A. Mitrukova, A.N.NechayScopusВАКRSCIMathSciNetzbMATH -
Approximate Weak Solutions to the Vorticity Evolution Equation for a Viscous Incompressible Fluid in the Class of Vortex Filaments
This paper is concerned with the equation for the evolution of vorticity in a viscous incompressible fluid, for which approximate weak solutions are sought in the class of vortex filaments. In accordance with the Helmholtz theorem, a system of vortex filaments that is transferred by the flow of an...
2022 / O. S.Kotsur, G.A. Shcheglov, I.K.MarchevskyScopusВАКRSCIMathSciNetzbMATH -
Construction of Inhomogeneous Velocity Fields Using Expansions in Terms of Eigenfunctions of the Laplace Operator
In this paper we present a method for constructing inhomogeneous velocity fields of an incompressible fluid using expansions in terms of eigenfunctions of the Laplace operator whose weight coefficients are determined from the problem of minimizing the integral of the squared divergence. A number of ...
2022 / E.V.Vetchanin, E.A.PortnovScopusВАКRSCIMathSciNetzbMATH -
On a Change of Variables in Lagrange’s Equations
This paper studies a material system with a finite number of degrees of freedom the motion of which is described by differential Lagrange’s equations of the second kind. A twice continuously differentiable change of generalized coordinates and time is considered. It is well known that the equations ...
2022 / A.P. MarkeevScopusВАКRSCIMathSciNetzbMATH -
Rotation of a Planet in a Three-Body System: a Non-Resonant Case
We investigate the temporal evolution of the rotation axis of a planet in a system comprised of the planet (which we call an exo-Earth), a star (an exo-Sun) and a satellite (an exo-Moon). The planet is assumed to be rigid and almost spherical, the difference between the largest and the smallest...
2022 / O. M. PodviginaScopusВАКRSCIMathSciNetzbMATH -
On Stability of the Collinear Libration Point L1 in the Planar Restricted Circular Photogravitational Three-Body Problem
The stability of the collinear libration point L1 in the photogravitational three-body problem is investigated. This problem is concerned with the motion of a body of infinitely small mass which experiences gravitational forces and repulsive forces of radiation pressure coming from two massive...
2022 / B. S. Bardin, A.N. AvdyushkinScopusВАКRSCIMathSciNetzbMATH -
Numerical Orbital Stability Analysis of Nonresonant Periodic Motions in the Planar Restricted Four-Body Problem
We address the planar restricted four-body problem with a small body of negligible mass moving in the Newtonian gravitational field of three primary bodies with nonnegligible masses. We assume that two of the primaries have equal masses and that all primary bodies move in circular orbits forming a...
2022 / E.A. Sukhov, E.V. VolkovScopusВАКRSCIMathSciNetzbMATH -
On the Dumb-Bell Equilibria in the Generalized Sitnikov Problem
This paper discusses and analyzes the dumb–bell equilibria in a generalized Sitnikov problem. This has been done by assuming that the dumb–bell is oriented along the normal to the plane of motion of two primaries. Assuming the orbits of primaries to be circles, we apply bifurcation theory to...
2022 / P. S. Krasilnikov, A.R. IsmagilovScopusВАКRSCIMathSciNetzbMATH -
Mathematical Model of Satellite Rotation near Spin-Orbit Resonance 3:2
This paper considers the rotational motion of a satellite equipped with flexible viscoelastic rods in an elliptic orbit. The satellite is modeled as a symmetric rigid body with a pair of flexible viscoelastic rods rigidly attached to it along the axis of symmetry. A planar case is studied, i. e.,...
2022 / A.V. Shatina, M. I. Djioeva, L. S. OsipovaScopusВАКRSCIMathSciNetzbMATH -
Dynamics-Based Piecewise Constant Control of an Omnivehicle
We consider the dynamics of an omnidirectional vehicle moving on a perfectly rough horizontal plane. The vehicle has three omniwheels controlled by three direct current motors. We study constant voltage dynamics for the symmetric model of the vehicle and get a general analytical solution for...
2022 / G.N. Moiseev, A.A. ZobovaScopusВАКRSCIMathSciNetzbMATH -
A Nonholonomic Model and Complete Controllability of a Three-Link Wheeled Snake Robot
This paper is concerned with the controlled motion of a three-link wheeled snake robot propelled by changing the angles between the central and lateral links. The limits on the applicability of the nonholonomic model for the problem of interest are revealed. It is shown that the system under...
2022 / E. M.Artemova, A.A.KilinScopusВАКRSCIMathSciNetzbMATH -
Gravity Compensation for Mechanisms with Prismatic Joints
This paper is devoted to the design of gravity compensators for prismatic joints. The proposed compensator depends on the suspension of linear springs together with mechanical transmission mechanisms to achieve the constant application of force along the sliding span of the joint. The use of...
2022 / A.A. Demian, A. S. KlimchikScopusВАКRSCIMathSciNetzbMATH -
Sparse Node-Distance Coordinate Representation for Tensegrity Structures
In this work, a nonminimal coordinate representation of tensegrity structures with explicit constraints is introduced. A method is proposed for representation of results on tensegrity structures in sparse models of generalized forces, providing advantages for code generation for symbolic or...
2022 / S. I. Savin, R.R. KhusainovScopusВАКRSCIMathSciNetzbMATH -
Motion Control of a Spherical Robot with a Pendulum Actuator for Pursuing a Target
The problem of controlling the rolling of a spherical robot with a pendulum actuator pursuing a moving target by the pursuit method, but with a minimal control, is considered. The mathematical model assumes the presence of a number of holonomic and nonholonomic constraints, as well as the presence...
2022 / E. A. MikishaninaScopusВАКRSCIMathSciNetzbMATH